Wiper arm assembly having a locking catch and method of construction

Abstract

A wiper arm assembly and method of assembly thereof includes a mounting head and a wiper arm configured for relative rotation during assembly from a disassembled position to a shipping position, wherein the wiper arm and mounting head are locked against rotation toward the disassembled position once in the shipping position. The mounting head and wiper arm have locking surfaces configured for locked engagement with one another while in the shipping position. The locking surfaces are brought into engagement with one another by a force imparted by a spring while rotating the mounting head relative to the wiper arm from the disassembled position toward the shipping position. When in the shipping position, the locking surfaces confront each other and prevent the mounting head and the wiper arm from rotating back toward the disassembled position from the shipping position.

What is claimed is: 
     
       1. A method of assembling a wiper arm assembly, comprising the steps of:
 providing a mounting head having one of an axle or a hub, said hub comprising an open pocket for receipt of said axle for rotation therein, said mounting head having one end configured for attachment to a vehicle and an opposite end having opposite sidewalls with each of said sidewalls having a flat first locking surface extending therefrom in spaced relation from one another; 
 providing a wiper arm having the other of the axle or hub and having opposite sidewalls with a flat second locking surface extending laterally outwardly from each of said sidewalls, said flat second locking surfaces extending away from one another in spaced relation from one another; 
 attaching a spring to said mounting head and said wiper arm; 
 rotating said mounting head and said wiper arm relative to one another from a disassembled position toward a shipping position and causing said spring to initially increase in preload and said axle to be received in said hub; and 
 bringing said mounting head and said wiper arm into the shipping position by snapping said flat locking surfaces on said mounting head and said wiper arm into engagement with one another under a force imparted by said spring during said rotating step, and preventing said mounting head and said wiper arm from rotating back toward said disassembled position in a purely rotational movement via the engagement of said flat locking surfaces with one another. 
 
     
     
       2. The method of  claim 1  further including providing said wiper arm with said hub and said mounting head with said axle. 
     
     
       3. The method of  claim 2  further including providing said wiper arm with protrusions extending away from said sidewalls, said protrusions providing said second locking surfaces along one surface of said protrusions and providing front abutment surfaces along another surface of said protrusions. 
     
     
       4. The method of  claim 3  further including configuring said locking surfaces of said protrusions generally perpendicular to said front abutment surfaces of said protrusions. 
     
     
       5. The method of  claim 3  further including providing said mounting head with a mounting bottom surface and configuring said second locking surfaces to face toward said mounting bottom surface and configuring said abutment surfaces to face toward said one end. 
     
     
       6. A method of assembling a wiper arm assembly from a disassembled position to a shipping position, comprising the steps of:
 providing a wiper arm having a flat locking surface, a mounting head having a flat locking surface and a spring; 
 attaching the spring to said wiper arm and said mounting head; 
 imparting a preload in said spring by rotating said wiper arm and said mounting head relative to one another; and 
 bringing said flat locking surfaces of said wiper arm and said mounting head into snapping engagement with one another under said preload of said spring, said preload maintaining said flat locking surfaces in confronting abutment with one another while in said shipping position, said flat locking surfaces preventing said wiper arm and said mounting head from being rotated back toward said disassembled position under a purely rotational force in the absence of translating said mounting head direct away from said wiper arm along a straight linear path. 
 
     
     
       7. The method of  claim 6  further including providing said mounting head with one of a hub or an axle, said hub having a pocket extending from an open end configured to receive said axle to a seating surface, and providing said wiper arm with the other of said hub or said axle. 
     
     
       8. The method of  claim 7  further including providing said wiper arm with said hub and said mounting head with said axle. 
     
     
       9. The method of  claim 7  further including configuring one end of said mounting head for attachment to a vehicle and providing said locking surface of said mounting head at an end opposite to said one end. 
     
     
       10. The method of  claim 6  further including providing said mounting head with a substantially planar bottom surface for mounting engagement on a vehicle and configuring said locking surface on said mounting head to be substantially parallel to said bottom surface.